Carton forming method and apparatus



June 8, 1943. D. w. (:0? ETAL CARTON FORMING METHOD AND rmmwus FiledMarch 15, 1940 5 S'nets-Sheet 1 i NvENT oRs Don W C y Waler'l'. Edie?ATTORNEYS- June 1943. w. co Y E'rAL 2,321,562

' 'cAfi'roN FORMING METHOD AND 'APBARATUS i'Filed March 15, -1940 5Sheds-Sheet 2 June 8, 1943- D.-'w.' cOY 2,321 562 L CARTON FORMINGMETHOD AND Am ms Filed uaronis, 1940' 5 Shetsi-Sheef. 4

INVENTORS C10,- 77012627 J7me? W, W ATTORNEYS- Dora W June 8, 1943. D.w. COY ETAL CARTON FORMING METHOD AND APPARATUS Filed March 15, 1940 5Sheets-Sheet 5 mmms Don Walzier' Z 7' %%WJMTTO S Patented June 8, 1943CARTON FORMING METHOD AND APPARATUS Don W. Coy, Chicago, and

Forest, Ill., assignors to pany of America, Chicago, 11].,

1 Delaware Walter T. Bitter, River United Biscuit Coma corporation ofApplication March 15, 1940, Serial No. 324,032

11 Claims.

This invention relates to an improved method and apparatus for formingcartons, particularly paperboard cartons, and although not restricted inall respects to employment with cartons in which certain portions aresecuredby means of thermoplastic adhesive material, is directed in someaspects to the formation of such cartons.

The main objects of the invention are to provide an improved method andapparatus for forming cartons from prefabricated carton blanks; toprovide an improved method and apparatus for folding and securing inreceptacle form prefabricated blanks provided with adhesive material onpredetermined portions of the blanks; to provide an improved method andapparatus for folding into receptacle form prefabricated carton blankshaving thereon dried thermoplastic material which becomes soft and tackywhen subjected to heat; to provide in apparatus of the characterindicated means for effectively softening thermoplastic adhesivematerial without danger of scorching or burning the material-"of thecarton blank which carries the thermoplastic material; to provide amethod and apparatus of the character indicated which will operate atrelatively high speed and relatively quietly; and in general it is theobject of the invention to provide an improved method and apparatus forfolding into receptacle form prefabricated carton blanks.

Other objects and advantages of the invention will be understood byreference to the following specification and accompanying drawingssheets) wherein there is illustrated apparatus embodying a selected formof the invention and capable of performing the improved method offorming cartons.

In the drawings:

Figure 1 is a plan except that the right-hand end portion of themechanism is shown in section as indicated by the line l-l of Figure 3;

Figure 2 is a section onthe line 2-2 of Figure 1;

Figure 3 is a side elevation of the right-hand end portion of themechanism illustrated in Figure 1;

Figure 4 is a section on the line 4-4 of Figure 3;

Figure 5 is a perspective of a detail of construction also appearing inFigure 4.

Figure 6 is a section on the line 6-6 of. Figure 1;

Figure '7 is a section on ure 6;

Figure 8 is a perspective of a carton blank the line 'I-'| of Figtypicalof the blanks which the apparatus illustrated is adapted to fold intoreceptacle, form;

Figure 9 is a perspective of a receptacle formed by the method andapparatus herein referred to from the blank illustrated in Figure 8;

Figures 10 andnll are perspectives illustrating different positions ofthe folding mechanism; and

Figure 12 is a section on an enlarged scale on the line l2--l 2 ofFigure 4.

Referring now. to the drawings, the carton blank which the disclosedapparatus is designed to fold into receptacle form is formed of asuitable weight of paper or cardboard and comprises a generallyrectangular member provided with creasing indicated by broken'linesindicated at 15 to divide the blank into a bottom-forming portion l'l,side wall forming portions l8, l8, corner-forming portions I9, 19 whichextend integrally from the ends of the side wall portions l8 and arefoldable along the crease lines l5, and end wall forming portions 20,20.

The end wall portions 20, 20 are provided on their inner faceswithadhesive material as indicated at 2l, the same being preferably of asuitable-thermoplastic composition which when 'dry is hard and free fromtackiness at ordinary temperatures. The thermoplastic adhesive materialis to be selected with regard to the kind of material to be packaged inthe receptacle, for example, if the product to be packaged is cheese orother materials which are flown into thereceptacle in more or lessliquid form at high temperature, then the thermoplastic material shouldbe such that it will not become soft or lose its adhesive propertiesuntil it is heated to a substantially higher temperature than that ofthe heated food product. Also, the material should be of such acharacter that it will not impart any flavor to the product packaged.Various thermoplastic materials may be produced which meet suchrequirements and they are considered preferable to conventional wetadhesives for many reasons well, known to those skilled in the art.

As indicated in Figure 9, the side walls l8, 18 are folded to upwardlyextending, right-angular relation to the bottom wall H, the cornerformthen folded inwardly from ing flaps l9, l9 are the respective sidewalls and the end walls 20, 20 are then folded upwardly intowall-forming position overlapping the outside of the said cornerformingflaps I9. The adhesive material 2|, if of thermoplastic character, ispreliminarily heated so as to render it soft and tacky so that when theend wall portions 20, 20 are folded upwardly and pressed against theflaps l9, l9, said shown in Figure 3. The

Q carton blank stock or the in asuitable refractory .and withoutexcessively lengthening the mechanism to 'hold -the carton in set-upcondition, means is provided in the described apparatus for chilling theadhesive material when the blank path of travel of the carton blanks.For this purpose, the said heating devices 33 are secured tween theheating is formed to receptacle condition as shown in Figure 9.

The mechanism herein disclosed comprises at its left-hand end as viewedin Figure 1, an arrangement such as a hopper designated 22 for receivinga stackof blanks of the type illustrated in- Figure 8, the same beingthen in flat condition,

having thereon the thermoplastic adhesive material indicated at 2|. Theblanks are fed one by one by suitable feeding mechanism not herein shownbut such as shown, for example, in Patent No. 1,979,253 to Coy, fordelivering the blanks one by one to a conveyor which propels the blanksto the folding mechanism. Such a conveyor is shown herein as comprisinga pair of endless chains 23, 23, the same being supported by suitablymounted sprockets such as indicated at 24. The conveyor chains 23, 23are continuously driven in unison and at a constant speed by a suitabledriving connection with a main-power shaft indicated at 25, suchconnection including, for example, a chain 23 which extends around asprocket carried by the power shaft 25, a sprocket carried by the shaft21 which carries .the conveyor chain sprockets at one end of theconveyor, and a sprocket carried by a shaft 23 as best conveyor chains23 are provided with suitable upwardly projecting ears or dogs 23, whichare adapted to engage the rear edge of a carton blank so as to propelthe same in unison with chains 23, 23.

The carton blanks are guided'in their travel on the conveyor chains 23,23 by means of angle iron side members 30, 30, the horizontal flanges ofwhich serve to support the opposite end portions of the blanks, and thevertical upstanding flanges of which serve to prevent sidewise shiftingof the blanks. A centrally disposed bar-like member 3| serves to supportthe carton blanks intermediate the conveyor chains 23, 23.

While the blanks are being propelled by the conveyor mechanism, thethermoplastic adhesive material carried by portions, of the blanks issubjected to heat for softening the material to a suitable tackycondition. For this purpose it is preferred to avoid direct contact witheither the thermoplastic material and means is provided for directingheat by radiation to the material to be softened. In this instance, suchmeans comprises two or more elongated electricel resistance heatingelements located at each side of the conveyor above the path of trawl ofthe opposite end portions of the carton blanks. Various forms ofelectrical resistance units may be employed and in this instance Icontemplate the use of commercially available carbon rod devices whichembody a carbon composition heating element 32 mounted body 32', soformed that it will reflect in the desired direction heat generated bythe carbon rod 32.

Such units are designated in their entirety 33 and each is mountedindependently of the other so as to be vertically adjustable relative tothe 75 the movement of the conveyor tothe upper ends of strapsdesignated 34, the lower ends of which are suitably slotted and clampedby means of bolts or cap screws 35 to a conveniently accessible framepart 38 which serves also to support the conveyor structure. It will beapparent that by varying the space bedevices 33 and the path of travelof the carton blanks a desirable control of the heating effect of thedevices is provided. Furthermore, by providing two or more independentlycontrollable electric units at each side of the structure, one or moreof the units may be shut oil, thereby aflording further control of theadhesive softening operation of the mechanism.

Although the heatin operation is, at present, preferably effected by themeans described, such means is not essential. Other heating means may besubstituted.- For example, heat may be applied by means of plates orshoes heated by any medium which will produce the required temperature.Such plates may, if desired, be positioned on the side of the blanksopposite the side on which the adhesive is applied, thereby to avoid anypossibility of direct contact with the adhesive material, or they may bemounted so as to be closely. adjacent but in sufllciently spacedrelation to the adhesive bearing side of the carton blanks to avoidcontact with the adhesive if such contact is to be avoided. However, insome cases 2 a wiping contacting arrangement may be preferable forvarious reasons.

The heating operation may also, for example; be effected by means of acurrent or blast of hot air directed over or against the adhesivebearing portions of the carton blanks.

It may be observed that the softening operation is dependent not onlyupon the temperature generated by the heating devices, the distancethereof from the material to be heated, the length of the heatingdevice, and similar variables of the selected heating device, but alsoupon the speed of travel of the carton blanks past said heating devices.The indicated variables are readily adjustable, whereas the speed oftravel of the conveyor and synchronized parts of the mechanism and theincidental variation in the production capacity oi the apparatus involvegreater diiflcuties, either with the carton forming apparatus or withthe resulting effect on. other operations in the plant wherein theapparatus is relied upon for cartons to meet a given productionschedule.

The heating of the carton blanks. incident to the adhesive softeningoperation, sometimes tends to cause the blanks to curl upwardly andthereby become disengaged from the ears or lugs 29 of the conveyingchains 23. To prevent or limit such curling, there are providedlongitudinally extending bars I25, I25 (see Figs. 1 and 2) which overliethe path of travel of the blanks near their ends but spaced laterallyfrom the adhesive bearing portions thereof. The number and location ofthe bars I25 may be varied in accordance with the requirements tocontrol the curling eil'ect in each case. The bars I25, I25 may bemounted in any suitable manner and in this instance they are verticallyadiustably suspended from cross I as shown at I23 which rest on theupper edges of the guide members 33, 30. The cross members may be freeof attachment to the guide members so as to facilitate removal of the,curl controlling structure, or they may be attached in fixed positionif desired. However, one practical arrangement contemplates anunattached arrangement wherein the cross members are provided withshoulders such as I21 for positioning the structure transversely of thepath of travel of the carton blanks. For adiustably supporting the barsI25, I25, the latter are suspended from the cross members by means ofscrews such as appear at I28, suitable springs I29 being provided forurging the bars to their lowest position as determined by the screws.

The conveyor chains 23, 23 deliver the carton blanks with thethermoplastic material thereon in tacky condition to folding mechanismwhich comprises a stationary outer forming member or die, and a seriesof inner forming members or mandrels designated 31 which are carried inpredetermined spaced relation by endless conveyor chains 38, 38 andconnecting bars 38'.

The conveyor chains v38, 38 extend around suitably journalled upper andlower sprockets 39 and 40, respectively, and they are continuouslydriven by means of intermeshing gears designated 4| 'behind the carton(Figs. 1 and 3) carried by the power shaft and the shaft on which thelower sprocket 46 is mounted. The travel of the inner form members 31 isguided at least in their operative zone by means of channel-like guidemembers 95, 95 in which the ends of the connecting bars 38 travel. Saidchannel-like members are carried by frame parts such as indicated at9|,*9| (see Fig. l)

The inner forming members 31 are of generally rectangular form and ofsuch size in cross-section that they will fit snugly within the cartonswhich are folded thereon. They are connected to the conveyor chain bymeans of relatively narrow ears 42 which are disposed rearwardly fromthe leading ends 43 of the inner form members.

The outer form or die comprises a transversely extending plate member 44at one side, and a pair of transversely spaced plate members 45 and 46at the opposite side. The upper ends of the said plates 44, 45 and 46are disposed in alignment with the surface of a table plate 41 overwhich the carton blanks are received from the conveyor 23. For properlylocating the carton blanks, one of which is indicated at B in Figure 6,over the ends of the forming plates 44, ,45 and 45, there are providedextensions 48 of the side guide flanges 30, and an abutment or stop 49spaced outwardly from the forming plates 45 and 45.

For effecting delivery of the carton blanks to the stop 49, there isprovided a reciprocating feeding device comprising a finger 50 pivotallymounted as shown at 5| on the lower end of an arm 52 which is mounted ona cross shaft 53, which in turn is pivotally mounted in suitable uprightframe or bracket part such as indicated at 54. The shaft 53 hasconnected to it an arm 55 which is connected by a link 55 to a crank pin51 carried by the continuously driven shaft 21.

A spring 58 or other suitable means is provided for normally urging thefinger clockwise direction about its pivot mounting 5| on the lower endof the arm 52, and the outer or free end of said finger is adapted toride in a groove'59 which is provided in the table plate 41. The free'end of said finger 50 is further provided with an upwardly andforwardly extending ear 59 which insures proper engagement of the edgeof the carton with the end of the finger 50 from which said ear extends.

It will be apparent that incident to the rotation of the crank 51, thefinger 56 will be reciprocated. In its rearward or counter-clockwisemovement as viewed in Figs. 3 and 6, said finger will ride over a cartonbeing advanced by the 56 to rock in a conveyor 23 until the free end ofthe finger drops forward movement, the finger willtake up the feedmovement of the carton blank and advance it to predetermined positionagainst the stop 49.

One of the inner form members 31 next approaches the carton blankdisposed over the outer forming member plates 44, 45 and 46 and serves.incident to its entrance between the plates, to fold the blank intoU-shape form in which the side walls l8, l8 extend upwardly relative tothe bottom wall H which is then disposed against the bottom or leadingend 43 of the inner forming member.

Incident to such upward folding of the side walls |8, |8, thecorner-forming flaps l9, l9 are also folded upwardly and they are nextsubjected to a folding operation which turns inwardly into the positionillustrated in Figure 9. Such inward folding is effected by means offolding members 6| and 62, respectively, pivotally mounted on theadjacent sides of the outer forming member and provided near their upperends with foldingears 63 arranged to engage the corner flaps l9 of thecarton blank at the opposite ends of each of the side walls l8, l8.

Said folding members 6| and 62 are simultaneously actuated in oppositedirections by means of a cam 54 carried by the power shaft 25 andoperating against a roller 65, carried by one arm of a pivoted bellcrank 65, the other arm of wh ch is connected by means of a link 61 toan arm 58 which is secured to a shaft 59 which carries the flap-foldingmember 6|.

, The shaft 69 is interconnected with the shaft 10 which carries thefolding device 52 by means of arms 1| and 12 and a link 13 as best shownin Figure 3. provided for causing the cam-following roller 55 tamaintain contact with the periphery of the cam To prevent interferenceby the end wall portions20, 20 of the carton blank with the foldingmovement of the corner flaps l9, l9, said end walls 28, 20 aretemporarily deflected to a downwardly inclined position as illustratedin Figure 11. The means for so deflecting the end wall portions 20comprises rods 15, 15 which are aligned vertically with the normalposition of the end wall portions of the carton blank when in operativerelation to the forming dies. Said rods are carried by members indicatedat 15 which are rigidly secured to a cross shaft-11, thelatter beingrotatably mounted in the adjacent ends of arms such as 18 which arepivotally mounted at their opposite ends as indicated at 19 in portionsof the frame members 54 provided for that purpose.

One of the arms 18 has connected to it through its pivot shaft 19, anarm 80 which is provided at its opposite ends with a roller 8| forengaging a rotary cam 82 carried by the driven shaft 21. The weight ofthe arms 86 and 18 and parts carried by their outer ends urges the armto swing downwardly in a clockwise direction, causing the roller 8| tomaintainoperative engagement with the cam periphery 82, so that incidentto rotation of the cam 82 said arms 89 and 18 and the parts carriedthereby are oscillated, the rods 15 being thereby reciprocated in avertical direction. To maintain the rods 15 in a, substantially verticalI position at all times, the shaft 11 has rigidly secured to'it a link83 which extends upwardly and is pivotally connected as shown at 84 tothe blank. Upon its return or A spring 14 or other means may be ment, istransmitted from the ton end wall portions necting element width toseriously hinder the folding of' mediate its ends, the arm ll forcausing the cam-following roller 32 to mounted in portions of the framemembe It provided for that purpose. It will be apparent that theparallel arm arrangement II and connections therebetween serve tomaintain the deflecting rods in substantially vertical position at alltimes. a

It will be further observed cam 02 to the arm II, through the adjacentarm I! and link It to the immediate overlying arm 85 and thence throughthe shaft I to the arm 85, link 83 and arm II at the other side of theapparatus.

It being understood that the various cams and operating elementsreferred to are properly that rocking moveon the outside of the arms IIwhich are in turn is suitably pivotally equipped with means for foldingupwardly the end wall portions 20, into overlapping relation flaps I,I8. such devices being caused to operate incident to the down-' wardmovement of the partially folded blank on the end of the inner memberll.

Said end wall folding devices comprise the upper ends 96, 96 of platemembers 91, 91, which timed in their operation, it will be apparent thatthe cam I2 is so adjusted the depressing rods II to move downwardly todeilect the carton blank end portions II, II as shown in Figure 11, justprior to the time the cam 64 actuates the folding devices I and 52.Adjustment of the extent ofdeflection of the carmay be made by adjustingthe vertical position of the rods 15, II in the holders it, by modifyingthe cam .2, or by other well known means. The timing of the operation ofthe deflecting members ll, 18 and the folding members ii and i2 is soadjusted that these parts operate immediately after the II, It arefolded upwardly on the inner forming member 31 and during the con tinuedtravel of the same.

The space between the folding plates 45 and 43 through which the innerform; member con- 42 passes is not of sufllcient the side wall ll of thecarton since the carton blanks are creased to facilitate such folding.However, it is preferred that means be provided forkeeping the upperfolding edge between said plates "and II and bers 45 and 48 and whichmember I! is of such 1 ofthe apparatus (see Figures 1 and 6).

roller 92 which is adapted to carried by the rotatably driven shaft 28.The cam 93 is so shaped and it timed relation to the operation of themechanism that the member 81 will be moved into operative relation withthe folding plate members 45 and 6 before the inner forming member 31.reaches its operative relation to the folding structure and so that themember 81 is withdrawn in ample time to permit the connecting neck orear I! and other parts to travel downwardly through their normal path ofmovement. A spring 94 or other suitable means is providedmaintainoperative contact The outer die or with the cam 83. forming member isalso and formed as to cause side wall portions,

the side wallsof extend transversely between depending extensions of theside folding plates 44 and 45, 46, the upper ends of which platesconstitute the means for efl'ecting upward folding of the side wallportions It, ll of the carton blank. It

when the inner forming will be apparent that member 31 carries thecarton blank downwardly between the upper ends of the plates 91, 91, theend walls 20, 20 of the carton blank will be folded upwardly intooverlapping relation. to the previously'in-folded flaps l9, IS.

The plates 91, 91 at opposite ends of the path of travel of the foldedcarton blank or receptacle may be disposed in such position that theypress the end walls' 20, 20 into tight contact with the underlyingflapsl9, I! so as to produce an effecdrag against the hesive material.

' rection that their respective rollers tive bond between theoverlapping parts through the agency of the reactivated thermoplasticad- However, th application of manner would create a serious advancingmovement of the inner form member with the receptacle thereon, and theaction incident to such a drag is somewhat objectionable for otherreasons. In this instance there is provided a series of pressure rollersrespectively designated SI for cooperation with each end of the innerform member 31. Said pressure rollers are Journalled as indicated at 99in suitable brackets Ill. (see Figures 4, 7 and 10) and each bracket I"is pivotally mounted as indicated at ill in the adJacent side membersl4, l5 and 46.

The axis of the pressure in such a meat of the respective brackets 100about their pivot mountings will effect movement of the respectiverollers toward or from the adjacent sides of the inner forming member31. purpose of urging the rollers 98, 98 toward the adjacent sides ofthe inner form member 31 Figure 4, that expansion of the springs ll!serves to cause the adjacent brackets ill. to rock in such a ditowardthe inner forming member 31. able means for limiting the extent of suchinward movement may be provided in the form of adjustable set screws Illwhich are adapted to engage suitably provided frame or other por-' tionssuch as indicated at I M.

It will be apparent that sively engage the receptacle formed on theleadton structure by the selection and insertion of springs I02 of thedesired strength.

During the travel of the receptacle between the pressure rollers tosqueeze the overlapping carton portions tightly together. To insurepermanence of the bond effected by I the moving receptacle carried bythe thermoplastic adhesive material, it is preferred that the samelapping carton portions are relieved from all pressure. For this purposethere are provided chilling shoesor blocks I05, I05 respectivelyassociated with the opposite series of pressure rollers 00, 90 (seeFigures 4 and 12). Each such shoe has its inner face finished to suchsmooth ness 'as to avoid the creation of too much drag on the innerform-- ing member 31 and thereceiving ends of said shoes are relieved asindicated-at I06, so as to facilitate entrance of the form-carriedreceptacle between theshoes.

Each shoe I05-is mounted between the respectively adjacent side plates44, 45 and 48 for'movement bodily toward and from the path of travel oi.the inner forming member. For this purpose there are provided links suchas indicated at I01, I01, at opposite sides of each shoe, such linksbeing pivotally mounted as indicated at I00. I08 at their upper ends inthe said side plates 44, 45 and 45 and having their lower ends pivotallyconnected as indicated at I09, I09 to the shoe intermediate its upperand lower ends. A spring I I is interposed between each shoe I andanother frame or similar portion III, such spring serving to normallyurge the shoe to move inwardly toward the path of travel of the innerforming member 31. The extent of such inward movement may be limited bysuitable adjustable stop screws H2, H2 which are spective shoes and fitslidably through suitable openings in said frame portions II I.

For cooling the shoes I05. they are provided with suitably formedinternal passageways such as indicated at 3 which are provided withinlet and outlet conduits I [4, 4, whereby water or other cooling mediummay be circulated through the said passageways. Theconduits I I4, I I4may include at some suitable point a flexible hose or other connectionwhich willpermit free movement of the shoes inwardly and outwardly.

When the inner forming member 31 with a receptacle formed thereonemerges from between the cooling shoes I05, I05, the receptacle is readyto be stripped from the inner forming member 31, the thermoplasticadhesive material having then been set sufiiciently to maintain thereceptacle in its set-up condition.

For stripping the receptacles from the inner forming member 31, thereare provided in association with the opposite sides of the inner formmember 31, endless chain or belt conveyor members I I5, I I5 which arecarried by suitable means such as upper and lower sprockets H5 and 1,respectively, such sprockets being suitably rotatably mounted in frameparts as best shown in Figures 3 and 4 of the drawings.

The conveyors H5, 5 are so arranged that one reach of each conveyortravels downwardly in outwardly spaced but substantially parallelrelation to the travel of the respectively adjacent sides of the innerforming member 31 and they are continuously driven at a speed of travelwhich is substantially higher than the speed of travel of the innerforming member 31. Each conveyor is provided with a suitable resilientfinger H8 having a laterally extending head or lip H9 at its upper endwhich is adapted to engage the upper edge I20 of the respectivelyadjacent end walls of the receptacle on the inner forming member. Eachof said fingers I I8 is so arranged that the inner ends of theirrespective lips H9 will first engage the adjacent sides of the innerthreaded into the re-' be chilled before the over- 4 between the fingersH8, H8 and form 31 somewhat above the said edges of the end walls of thereceptacle and incident to the higher speed of travel of the conveyorsH5, II 5, the lips of said fingers will engage said receptacle edges andultimately pull the receptacle from the end of the inner forming member31. The receptacle, 'of its own weight, will drop from may be receivedby a conveyor or other preferred means.

For driving the conveyors H5, H5, there is provided a shaft I2I suitablyJournalled in the frame work of the apparatus and connected by pairs ofbevelled gears indicated at I22, I22 to the shafts I23 which carry thelower sprockets III. The shaft I2I is in turn driven by a chain I24which engages suitable sprockets carried by the shaft |2I and anotherdriven shaft such as the shaft 21. The speed at which the conveyors II5, I I5 are driven may be determined by proper selection of sprocketswhich cooperate with the chain I24 and by proper selection of theintermeshing gear pairs I22, I22. In this instance, the sprocket on theshaft I2I which is driven by the chain I24 is of much smaller pitchdiameter than the driving sprocket on the shaft 21, so that the speed ofrotation of the shaft IN is increased to effect the desired result.

The described apparatus, being continuous in operation and being freefrom noisy operating reciprocating mechanism, is both rapid and quiet inoperation. Because of its improved arrangement for applying pressure tothe overlapped parts of the receptacle, it has been found to be highlyefficient in the forming of cartons .which employ thermoplastic adhesivematerial for effecting the bond between such overlapping parts and itsarrangement for chilling-the adhesive material to set the same after theextended application of pressure contributes materially to itssuccessful operation.

Although the apparatus as shown is arranged for setting up prefabricatedcarton blanks, it will be apparent to those skilled in the art thatinstead of providing mechanism for feeding such prefabricated blanks,mechanism for forming such blanks may be substituted, such mechanismthen including means for applying the thermoplastic adhesive material tothe selected portions of the carton blanks. In such a case, theemployment of the heating units 33 may possibly be dispensed with,although even in such case they maybe desirable for the purpose ofmaintaining the adhesive material in its tion until the carton blankreaches the folding elements of the apparatus.

Many changes in the structure may be made without departing from thespirit of the invention, the scope of which should be determined byreference to the following claims, the same being construed as broadlyas possible, consistent with the state of the art.

I claim:

1. The method of forming a carton which comprises the steps of providingprefabricated carton blanks having thermoplastic adhesive material onpredetermined portions of the blanks, propelling the carton blanksedgewise, effecting softening of the adhesive material by directingradiated heat thereto during the travel of the blanks and then, whilethe adhesive remains soitand tacky, folding the blanks-into receptacleform and pressing together the portions thereof to be united by saidadhesive.

2. Apparatus for forming cartons employing thermoplastic material foradhesively unitin most desirable tacky condiv overlapped portionscomprising meins for pro-- pelling carton blanks having thereon driedthermoplastic material, heat radiating means disposed adjacent but inspaced relation to the path a of travel of the blanks for radiating heatto said dried thermoplastic material so as to soften the same to tackycondition, means for adiustably a,sa1,sea

mounting said heating means for movement toward and from said path oftravel, thereby to facilitate regulation of the softening eiiect of saidheating means, means for folding the blanks to receptacle form withpredetermined portions overlapping the adhesive-bearing portions, and

means for resiliently pressing together said overlapping portions.

3. Apparatus for forming cartons embodying thermoplastic material foradhesively uniting overlapped portions comprising means for protheblanks to receptacle form with predetermined portions overlapping theadhesive-bearing portions, means for resiliently pressing together saidoverlapping portions, means for chilling and thereby setting theadhesive between said overlapping portions, said chilling meanscomprising a presser member mounted for movement toward and from theoverlapped portions of the carton, means yieidingly urging said pressermember to ward said overlapped portions, means for limiting suchmovement, and said presser member being provided with a passagewaytherein for the circulation therethrough of a cooling medium.

4. In apparatus of the class described, means for forming and propellingcartons, mechanism for applying pressure on overlapped carton portionscomprising a pair of side plates, a pluralit of relatively independentbrackets pivotally mounted on said side plates, a roller iournalled ineach of said brackets on an axis eccentric with the pivot axes oi therespective brackets, spring means acting on said brackets to urge thesame to rock in such direction as to urge the respective rollers againstsaid carton portions, means for limiting the spring-eil'ected movementof said rollers, and a pressure block for engaging said portions afterthe same pass said rollers, said pressure block being mounted in saidside plates for movement bodily toward and from said, overlappedportions, spring means for urging said block toward said overlappedportions, means for limiting the spring-effected movement of said block,and said block being provided with a passageway therein for thecirculation therethrough of a heat-exchanging medium.

5. Apparatus for forming cartons comprising an outer forming member, aninnner forming member adapted to move continuously in a predetermineddirection through said outer member to cooperate therewith to foldwalleforming por tions of a carton blank into receptacle-formingposition relative to another portion of the blank, means independent ofsaid outer member for folding corner-forming flaps of the blank intoreceptacle-forming position, reciprocable means movable in the directionof movement of said inner member for moving certain wall-formingportions of the blank out of the way of said flaps during the foldingmovement thereof, and means for folding said last mentioned portionsinto wall-forming position overlapping sa d fo ded flaps.

"6. Apparatus for forming cartons comprising an outer forming member, aninner :iorming member adapted to'move continuously iii' a predetermineddirection through said outer member for cooperation. therewith infolding carton blanks into receptacle-forming condition, means forpropelling said inner forming member comprising a continuously propelledendless conveyor. an ear spaced rearwardly from the leading end of saidinner member, projecting laterally therefrom and secured to saidconveyor for interconnecting said inner member and conveyor, said outerforming member being provided with a slot in a portion thereof forpermitting the passage therethrough of said ear, auxiliary outer formingmember meansadapted to be inserted in said slot to complete said outerforming member so. as toprovide continuous-forming surfaces forcooperation with the leading end of said inner member, means formounting said auxiliary member for movement into and out vofsaid slot,and means for efiecting such movement of said-auxiliary member in timedrelation with the travel or said inner member through said outer member.v

'7. Apparatus 1'or forming cartons employing thermoplastic material foradhesively uniting overlapped portions comprising means for propellingcarton blanks having thereon dried thermoplastic material, heating meansfor softening to tacky condition said thermoplastic material, saidheating means comprising two or more elongated electrical resistancedevices arranged longitudinally of said propelling means so' as to beadapted to successively heat carton portions propelled therepast, saidelectrical devices being adjustably mounted in spaced relation to thepath of travel of said carton blanks so as to eifect softening of saidthermoplastic material by heat radiated from said devices, the heatingeflect of said heating means being controllable by the capacity 01' eachheating element to be turned on or of! independently of the other and bythe adjustability of the spacing of the heatingmembers relative to thepath of travel of the carton blanks, means for folding the blanks toreceptacle form with portions thereof overlapping the adhesivebearingportions, and means for pressing together said overlapping portions.

8. Apparatus for forming cartons employing thermo-plastic material foradhes'ively uniting overlapping portions, comprising means forpropelling carton blanks having thereon dried thermo-"plastic material,an electrical. resistance device arranged longitudinally of saidpropelling means, so as to be adapted to heat carton portions propelledtherepast, so as to eflect softening of said thermo-plastic material byheat rapelling carton blanks having on portions thereof driedthermo-plastic material, an electrical resistance device extendinglongitudinally of said propelling means and disposed in-spaced relationto the path of travel of the blanks carried by said propelling means toeffect softening of said thermo-plastic material by heat radiated fromsaid device when energized, means for folding the blanks to receptacleform with portions thereof overlapping the softenedthermo-plastic-bearlng portions, and means for holding together saidoverlapping portions while said softened thermoplastic material sets.

10. Apparatus for forming cartons employing thermo-plastic material foradhesively uniting overlapping portions, comprising means for propellingcarton blanks having on portions thereof dried thermo-plastic material,a carbon rod electrical resistance device extending longitudinally ofsaid propelling means and disposed in spaced relation to the path oftravel of the blanks carried by said propelling means to effectsoftening of said thermo-plastic material by heat radiated from saidcarbon rod device when energized, means for folding the blanks toreceptacle form with portions thereof overlapping the softenedthermo-plastic bearing portions, and means for holding together saidoverlapping portions while said softened thermo-plastic material sets.

11. Apparatus for forming cartons employing thermo-plastic material foradhesively uniting overlapping portions, comprising means for propellingcarton blanks having thereon dried thermo-plastio material, heatradiating means disposed adjacentbut in spaced relation to the path oftravel of the blanks for radiating heat to said dried thermo-plasticmaterial so as to soften the same to tacky condition, means for foldingthe blanks to receptacle form with portions thereof overlapping theadhesive-bearing portions, and means for holding together saidoverlapping portions while said softened thermo-plastic material sets.

7 non w. COY.

WAL'I'ER T. amen

